5-Phenoxyphenyl-tetrahydro-1,3,5-thiadiazin-4-ones

Abstract

The invention relates to novel substituted 5-phenoxyphenyl-tetrahydro-1,3,5-thiadiazin-4-ones of the formula <IMAGE> (I) wherein R1 is hydrogen, halogen, C1-C4-alkyl, trifluoromethyl, methoxy, ethoxy, benzyl, phenoxy, phenylthio, or phenoxy or phenylthio substituted by a radical selected from the group consisting of halogen, C1-C4-alkyl, methoxy and ethoxy; each of R2 and R3 independently of the other is hydrogen, halogen, C1-C4-alkyl, trifluoromethyl, methoxy or ethoxy; each of R4 and R5 independently of the other is hydrogen or C1-C6-alkyl; and each of R6 and R7 independently of the other is C1-C4-alkyl, trifluoromethyl, C3-C6-cycloalkyl, alkoxyalkyl containing a total of 2 to 6 carbon atoms, benzyl, phenyl or phenyl which is substituted by a member selected from the group consisting of halogen, C1-C4-alkyl, methoxy and ethoxy, to the preparation of these novel compounds and to compositions containing them for use in pest control, especially for controlling insects and representatives of the order Acarina which are pests of plants and animals. The novel compounds are particularly effective against larval stages and nymphs of plant-destructive feeding insects, and most particularly against plant destructive cicadas, especially in rice crops.

What is claimed is: 
     
       1. A compound of the formula I ##STR100## wherein R 1  is hydrogen, halogen, C 1  -C 4  -alkyl, trifluoromethyl, methoxy, ethoxy, benzyl, phenoxy, phenylthio, or phenoxy or phenylthio substituted by a radical selected from the group consisting of halogen, C 1  -C 4  -alkyl, methoxy and ethoxy; each of R 2  and R 3  independently of the other is hydrogen, halogen, C 1  -C 4  -alkyl, trifluoromethyl, methoxy or ethoxy, each of R 4  and R 5  independently of the other is hydrogen or C 1  -C 6  -alkyl; and each of R 6  and R 7  independently of the other is C 1  -C 4  -alkyl, trifluoromethyl, C 3  -C 6  -cycloalkyl, alkoxyalkyl containing a total of 2 to 6 carbon atoms, benzyl, phenyl or phenyl which is substituted by a member selected from the group consisting of halogen, C 1  -C 4  -alkyl, methoxy and ethoxy, or a salt thereof. 
     
     
       2. A compound of the formula Ia according to claim 1 ##STR101## wherein R 1  or R 7  are as defined for formula I in claim 1. 
     
     
       3. A compound according to claim 1 of the formula I or according to claim 2 of the formula Ia, wherein R 1  is hydrogen, halogen, C 1  -C 4  -alkyl, trifluoromethyl, methoxy, benzyl or phenoxy; each of R 2  and R 3  independently of the other is hydrogen, halogen or C 1  -C 4  -alkyl; each of R 4  and R 5  independently of the other is hydrogen or C 1  -C 4  -alkyl; and each of R 6  and R 7  independently of the other is C 1  -C 4  -alkyl, C 3  -C 6  -cycloalkyl, alkoxyalkyl containing a total of 2 to 4 carbon atoms, phenyl or phenyl which is substituted by a member selected from the group consisting of halogen and C 1  -C 4  -alkyl. 
     
     
       4. A compound according to claim 3 of the formula Ia, wherein R 1  is hydrogen, chlorine, methyl, trifluoromethyl, methoxy, benzyl or phenoxy; R 2  is hydrogen, chlorine or methyl; R 3  is hydrogen; each of R 4  and R 5  independently of the other is hydrogen or C 1  -C 4  -alkyl; and each of R 6  and R 7  independently of the other is C 1  -C 4  -alkyl, cyclopropyl, phenyl, or chlorophenyl. 
     
     
       5. A compound according to claim 4 of the formula Ia, wherein R 1  is methyl, trifluoromethyl or benzyl; R 2  is hydrogen or methyl; R 3  is hydrogen; each of R 4  and R 5  independently of the other is methyl or ethyl; and each of R 6  and R 7  independently of the other is C 3  -C 4  -alkyl. 
     
     
       6. A compound according to claim 5 of the formula ##STR102## 
     
     
       7. A compound according to claim 5 of the formula ##STR103## 
     
     
       8. A compound according to claim 5 of the formula ##STR104## 
     
     
       9. A compound according to claim 5 of the formula ##STR105## 
     
     
       10. A compound according to claim 5 of the formula ##STR106## 
     
     
       11. A compound according to claim 5 of the formula ##STR107## 
     
     
       12. A composition for controlling plant destructive insects and representatives of the order Acarina, which contains as active component a compound as claimed in any one of claims 1 to 11, together with suitable carriers and/or other adjuvants. 
     
     
       13. A method of controlling plant destructive insects and representatives of the order Acarina, which comprises applying to said insects or to the locus thereof a pesticidally effective amount of a compound as claimed in any one of claims 1 to 11. 
     
     
       14. A method according to claim 13, wherein the pests to be controlled are plant-destructive cicadas. 
     
     
       15. A method according to claim 14, wherein the pests to be controlled are cicadas in rice crops.